1. Field of the Invention
This invention is related to the field of valves, and more particularly to leakproof valves which can only be opened and closed by their state of engagement or disengagement with particular mating valves, to thereby eliminate the possibility of a valve being accidentally opened when it is not connected to a proper mating valves, to therefore prevent the accidental release of fluid into the environment.
2. State of the Prior Art
There are many different styles of valves for use in controlling the flow of fluid between different points in a system. These include gate valves, ballcock valves, and quick connect snap together style valves, which are used to gain pneumatic hoses, such as are widely used in auto repair garages. While snap together valves are acceptable for air, they are not acceptable for fluids, since some fluid escapes when the two mating parts of the valve are connected or disconnected. In the case of fluids such as oil, any such leakage is unacceptable.
In the field of motor oil changing for vehicles, the traditional method to conduct an oil change has been to remove the oil pan drain bolt, allow the oil to drain by gravity into a collection pan or drum, replace the oil drain pan bolt, and then refill the oil drain pan with clean motor oil. The co-inventor herein James E. Clark has invented a vehicle waste oil recovery and delivery system to remove old oil and delivery new oil to a vehicle for which U.S. patent application Ser. No. 08/271,268 entitled "Vehicle Oil Waste Recovery and Delivery System" is pending. In this system, a spring actuated oil pan drain valve is screwed into the oil pan in lieu of an oil pan drain bolt, and an oil evacuation line is connected to the oil pan drain valve to evacuate old oil from the vehicle's oil pan. Such an oil pan valve is manufactured by Femco, of Amsterdam, Netherlands. Thereafter, new oil is added to the vehicle. However, even with this advanced system, on occasions, some users have inadvertently attempted to remove the waste oil evacuation line before all the waste oil is removed from the oil drain pan, which has resulted in spillage.
There accordingly remains a need for a leakproof valve which can only be opened and closed by its state of engagement or disengagement with an oil drain valve or another particular matting fitting on a vessel or supply of fluid from which fluid will be transferred.